ERROR: Failed building wheel for jsonnet & mujoco-py

[RileyChing]

when i clone the mujoco-worldgen repository and install it by pip install -r mujoco-worldgen/requirements.txt, the following error appears:
_ERROR: Command errored out with exit status 1:
command: /Users/apple/opt/anaconda3/envs/python36/bin/python -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/private/var/folders/f9/75c_fx_91_783vzltv3rtzx40000gn/T/pip-install-nm6mylep/jsonnet/setup.py'"'"'; file='"'"'/private/var/folders/f9/75c_fx_91_783vzltv3rtzx40000gn/T/pip-install-nm6mylep/jsonnet/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(file);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, file, '"'"'exec'"'"'))' bdist_wheel -d /private/var/folders/f9/75c_fx_91_783vzltv3rtzx40000gn/T/pip-wheel-_3rt2mth
cwd: /private/var/folders/f9/75c_fx_91_783vzltv3rtzx40000gn/T/pip-install-nm6mylep/jsonnet/
Complete output (31 lines):
running bdist_wheel
running build
running build_ext
xcrun: error: invalid active developer path (/Library/Developer/CommandLineTools), missing xcrun at: /Library/Developer/CommandLineTools/usr/bin/xcrun
Traceback (most recent call last):
File "", line 1, in
File "/private/var/folders/f9/75c_fx_91_783vzltv3rtzx40000gn/T/pip-install-nm6mylep/jsonnet/setup.py", line 75, in
test_suite="python._jsonnet_test",
File "/Users/apple/opt/anaconda3/envs/python36/lib/python3.6/site-packages/setuptools/init.py", line 161, in setup
return distutils.core.setup(**attrs)
...
File "/Users/apple/opt/anaconda3/envs/python36/lib/python3.6/distutils/dist.py", line 974, in run_command
cmd_obj.run()
File "/private/var/folders/f9/75c_fx_91_783vzltv3rtzx40000gn/T/pip-install-nm6mylep/jsonnet/setup.py", line 54, in run
raise Exception('Could not build %s' % (', '.join(LIB_OBJECTS)))
Exception: Could not build core/desugarer.o, core/formatter.o, core/libjsonnet.o, core/lexer.o, core/parser.o, core/pass.o, core/static_analysis.o, core/string_utils.o, core/vm.o, third_party/md5/md5.o

ERROR: Failed building wheel for jsonnet_

I tried a lot of ways and it didn't work, it would be great if you can help.